The invention relates to a trap and in particular to a single-kill trap for use in controlling pests such as possums.
The trapping of animals for food, research and pest control is well known. Both live-capture and kill traps are used, depending on the aim of the trapper. Traps that are designed to be lethal are typically required to kill within a certain limited time period to avoid undue suffering to the animal caught in the trap.
In areas where a particular species is released from its usual population controls, either through a change in the local environment or introduction into a new environment, that species may breed prolifically, affecting surrounding plant and animal life. Such effects often have significant cultural and commercial repercussions resulting in focused efforts to eradicate or at least control the pest.
In New Zealand, one of the most prolific and environmentally destructive pest species is the possum, introduced from Australia in the mid 1800""s to establish a fur trade. The possum population in Australia is limited by predators, bush fires and a less bountiful food supply, none of which impact on the possum in New Zealand. Other introduced (intentionally or otherwise) animals that have become pests include mustelids (ferrets, stoats and weasels), rats, cats (domestic or wild) and dogs (domestic or wild).
While existing pest control methods are successful, they invariably have their Limitations. For example, the traps currently used, such as the Timm""s trap (described in NZ 207241 as outlined below) and the xe2x80x9cConibearxe2x80x9d style of trap, are too bulky to carry in large numbers or need a special enclosure built to house them.
There is a need in the art for a trap that is lightweight, compact and that requires no additional housing.
New Zealand Patent Specification 238559 teaches of a possum trap having two telescoping cylinders, the lower of which has an aperture through which the possum places its head to reach bait. In reaching the bait the possum""s head pushes a depending arm which releases a catch allowing the upper cylinder to drop, preferably under spring bias. This catches the possum""s neck between the rim of the upper cylinder and the bottom of the aperture, throttling it.
New Zealand Patent Specification 189654 also discloses a trap consisting of two telescoping cylinders, each having a hole which are in register when the trap is set. When an animal places its head through the holes and reaches for and moves a baited trigger, a locking bar is released allowing the two cylinders to move relative to each other catching the animal around the neck and killing it.
New Zealand Patent Specification 238499 describes a possum trap with a spring loaded linearly moveable blade. When a possum enters the trap and pushes on a trigger plate the blade is released and severs the possum""s neck.
New Zealand Patent Specification 207241 discloses a possum trap comprising a hollow housing with an opening providing access to a baited trigger. When the trigger is moved xe2x80x9cover-centrexe2x80x9d by a possum taking the bait a trigger pin pivots and releases a spring biased impact bar which is pulled rapidly upward trapping the possum""s head in the opening and stopping air and blood circulation.
U.S. Pat. No. 5,010,682 teaches of an animal trap including a spring with biased apart first and second arm members extending outwards from the spring. A loop on the first arm member encircles a jaw portion on the second arm member which is biased towards a side of the loop. When a trigger is pushed, the second arm member is released catching an animal""s head and throttling it between the jaw portion and the loop.
The disadvantages of the prior art traps discussed above are that they are generally too bulky and heavy to store or carry in large quantities conveniently or they require an enclosure to be built or located to house them in use.
It is therefore an object of the invention to provide a light weight, compact, effective single-kill trap; and/or to overcome or address at least one of the disadvantages of the prior art; and/or at the least to provide the public with a useful choice.
According to a first aspect of the invention there is provided a single kill animal trap comprising:
a spring means comprising a substantially rectangular sheet of spring material folded transversely to be substantially C-shaped in longitudinal cross-section defining an upper surface, a lower surface and a back wall; whereby said upper surface and said lower surface are biased together, and wherein a portion of each of the upper surface and the lower surface is adapted to be a killing surface in use;
a setting means adapted to hold the upper and lower surfaces in an armed position; and
a trigger means positioned within the space defined by the upper and lower surfaces and the back wall of the spring means and co-operable with said setting means;
the trap being triggered when the trigger means is moved by an animal which in turn disengages the setting means allowing the killing surfaces to come together on a said animal therebetween.
Preferably the spring material is spring steel.
Preferably the trap has side panels that block entry to the side of the trap.
Preferably the side panels are transparent.
Preferably the trap further comprises a connecting means wherein the setting means is co-operable with the trigger means through said connecting means.
In a preferred embodiment of the first aspect of the invention the setting means comprises at least two arms pivotally attached to and projecting inwardly from each of the upper surface and the lower surface, each arm from the upper surface being pivotally connected to a corresponding arm from the lower surface to define a pivot point. Preferably the arms are attached to the upper or lower surface substantially adjacent the killing surface.
Preferably the trigger means comprises a lever arm comprising a trigger portion and a tab portion wherein said lever arm flexibly engages the back wall between said trigger portion and said tab portion so that said trigger portion extends into the interior of the trap and said tab potion protrudes behind the back wall whereby said tab portion is adapted to move the connecting means in use to release the setting means. In a highly preferred embodiment the trigger means comprises two lever arms wherein the trigger portions are flexibly engaged. Preferably the trigger portions are flexibly engaged by a bait means. Preferred forms of a bait means include, but are not limited to, a material such as wood or plastic that is impregnated with an attractant appropriate to attract the desired target species.
Preferably the connecting means comprises a substantially U-shaped connecting member wherein one arm of the member engages the setting means at each pivot point, whereby when the trap is set the base of the member is positioned substantially adjacent the tab portion or portions of the trigger means.
Preferably the upper and lower surface may be provided with attachment means for attaching the trap to a surface.
According to a second aspect of the invention there is provided a single kill animal trap comprising:
a spring means comprising a substantially rectangular sheet of spring material folded transversely to be substantially C-shaped in longitudinal cross-section describing an upper surface, a lower surface and a back wall;
upper and lower pairs of arms projecting from the back wall of the spring means;
upper and lower jaws affixed to upper and lower arms respectively, said jaws biased together by the spring means;
a pivot support frame comprising an elongated rod engaging and extending upwards from each lower arm adjacent the lower jaw and a cross-piece connecting the upper ends of said rods;
a pivot rod pivotally mounted on the cross-piece, the end of the pivot rod extending away from the back wall beyond the cross-piece to form a jaw rest, the other end of said pivot rod extending above the upper surface in the direction of said back wall; and
trigger means positioned within the space defined by the upper and lower surfaces and the back wall of the spring means, said trigger means engaging a connecting rod that engages a pivot rod;
the trap being armed when the upper jaw is pivoted to be engaged on the jaw rest and the other end of the pivot rod is retained by the connecting rod, trigger bar and catch; and being triggered when the trigger bar is released from the catch.
Preferably the spring material is spring steel.
Preferably the trigger means comprises a trigger bar positioned substantially parallel to said jaws and held in a set position by a catch. Preferably, said trigger bar slidably engages said connecting rod. Preferably said connecting rod projects through the upper surface of the spring means and in turn slidably engages the pivot rod.
In one preferred embodiment of the second aspect of the invention, the trap includes a secondary jaw member affixed to the upper arms between the upper jaw and the spring means. The secondary jaw is preferably a substantially W- or U-shaped member having upright arms and a mid-portion with the upright arms of the member attached to the upper arms of the trap so that when the trap is in an xe2x80x9cunsetxe2x80x9d or xe2x80x9ctriggeredxe2x80x9d position the mid-portion of the member projects at least partially below the plane defined by the lower arms.
The frame of the second aspect of the invention is preferably removably attached to the lower arms. This enables the trap to be dismantled into a compact form for transportation and storage. A preferred means of attaching the frame comprises socket members attached to the lower arms adjacent the lower jaw and adapted to receive the lower ends of the elongated rods of the frame.
In order to deter an animal entering the trap from the side and thus to ensure a clean kill it is preferable that a trap of the second aspect of the invention has side panels attached to the elongated rods of the pivot support frame that block entry to the side of the trap. Preferably the side panels are transparent so as to give the trap an xe2x80x9copenxe2x80x9d feel.
Preferably a trap of the present invention is baited by placing bait in the trap in such a position that an animal entering the trap will trigger the trap by reaching for the bait. One preferred form of bait comprises plastic impregnated with cinnamon and then suitably placed in the trap. An alternative bait is peanut butter, either fresh or impregnated in plastic.
Preferably a trap of the present invention is a colour attractive, or at least not repulsive, to the target animal.
It is preferable to provide a trap of the present invention with a locking means to keep the jaws closed after the trap is triggered. This aims to prevent the animal that triggered the trap from escaping.
This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
The invention consists in the foregoing and also envisages constructions of which the following gives examples.